1 Introduction.

This is a power analysis on the CPUE sampling program for the Quirk Creek watershed. A summary of the number of locations sampled by year is found in Table 1.

Table 1. Summary of locations and fish captured by year
Year Locations BKTR BLBK BLTR CTTR
1987 1 61 0 18 117
1988 2 0 0 0 7
2000 1 29 4 1 3
2006 3 1046 103 75 418
2007 2 624 23 81 371
2008 2 375 2 31 335
2009 2 94 0 2 161
2010 4 228 0 4 157
2011 2 219 2 5 220
2012 2 125 0 17 107
2013 2 110 4 12 76

A preliminary plot of the CPUE over time for each of the species is found in Figure 1.

2 Variance components

The variance components were estimated after fitting a linear mixed model to the CPUE on the logarithmic scale. A summary of the estimated variance components is found in Table 2.

Table 2 . Estimated variance components (log scale)
Species Sampling SD Process SD
BKTR 0.2 0.36
BLBK 1.36 0.88
BLTR 0.91 0.71
CTTR 0.27 0.48

3 Power analysis

A power analysis was conducted to detect a 10%, 30%, 50%, 100%, 200%, 300% change over 5 years by varying the number of sites given the sampling and process error estimated above. Results are summarized in Figure 2 (one plot per species).

4 Summary

Add text here summarizing the bleak results